The present invention relates generally to an internal combustion engine, and particularly to a two-stroke engine that utilizes a system for lowering the electromagnetic and radio frequency interference signature.
Internal combustion engines generally have one or more cylinders through which one or more pistons move in a reciprocating manner. Each piston is connected to a crankshaft by a connecting rod able to deliver force from the piston to the crankshaft to rotate the crankshaft. Power to drive the piston is provided by igniting a fuel-air mixture disposed in the cylinder on a side of the piston opposite the connecting rod. The fuel-air mixture is ignited by some type of ignition device, such as a spark plug.
Internal combustion engines typically utilize a variety of conductors, e.g. wires, for carrying various electronic signals. For example, an electronic control unit may receive a variety of signals from various sensors and output a variety of signals to, for example, an injection system and an ignition system. The ignition system also utilizes a variety of electric signals, including electric signals provided to the one or more spark plugs used to ignite a fuel/air mixture disposed in the combustion chamber. Typically, such electric signals provide an electromagnetic and radio frequency signature that can cause unwanted interference. In certain applications, it would be advantageous to reduce the electromagnetic interference and radio frequency interference produced by the electronics of the engine.
According to one aspect of the present invention, a low signature engine system is provided to reduce electromagnetic interference (EMI) and radio frequency interference (RFI). The system includes a two-stroke engine. The engine has a combustion chamber and an injector deployed in communication with the combustion chamber to discharge a fuel thereto. Additionally, the engine includes an electronic control unit in communication with the injector to control the discharge of fuel. Also, an EMI/RFI reduction system is used to lower the electromagnetic and radio frequency interference signature of a plurality of conductors utilized by the two-stroke engine during operation.
According to another aspect of the present invention, a method is provided for reducing the electromagnetic and radio frequency signature of an engine having a plurality of electrical conductors. The method comprises placing at least some of the plurality of electrical conductors into a bundle. The bundle is surrounded with a conductive layer. Additionally, a conductive strip is deployed intermediate the bundle and the conductive layer. The conductive strip is then grounded to reduce the EMI/RFI signature.
According to another aspect of the present invention, a method is provided for making an engine having a reduced electromagnetic and radio frequency signature. The method includes providing a two-stroke engine having a combustion chamber. The method further includes injecting a fuel directly into the combustion chamber during operation. Additionally, the method comprises limiting the electromagnetic and radio frequency interference by providing an EMI/RFI barrier around a plurality of electrical conductors.